1. Field of the Invention
The present invention relates to inclining and rotating table apparatuses.
2. Description of the Related Art
Inclining and rotating table apparatuses used in machine tools and the like are already well known. This inclining and rotating table apparatus has a driven turning shaft that is driven to turn by a drive source such as a motor or the like, and a rotary table device that is driven to turn by the driven turning shaft. The rotary table device has a driven rotating shaft that is driven to rotate by a drive source such as a motor or the like, and a rotary table that is for holding a workpiece or the like and that is driven to rotate by the driven rotating shaft.
In such an inclining and rotating table apparatus, when the driven turning shaft is driven by the drive source, the driven turning shaft turns, and a turning force of the driven turning shaft is transmitted to the rotary table device, which turns about the turning shaft. By the turning of the rotary table device, a table surface of the rotary table device is caused to incline. When the driven rotating shaft is driven by the drive source, the driven rotating shaft rotates, and a rotating force of the driven rotating shaft is transmitted to the rotary table, which rotates about the center of the rotating shaft (for example, see JP 2002-126958A).
In the above-noted inclining and rotating table apparatus, from the standpoint of reliably holding the rotary table device still, and from the standpoint of reliably holding the rotary table still, it is effective to provide clamping devices in the inclining and rotating table apparatus.
When the rotary table or the rotary table device has been positioned, these clamping devices clamp a movable section, for example, when the workpiece held by the rotary table is being machined. By doing this, it is possible to reliably keep the rotary table and the rotary table device still, and to perform high-precision machining of the workpiece.
When a clamping device is provided on an inclining and rotating table apparatus, it can be envisioned that the clamping device be provided on the turning shaft of the rotary table device or on the rotating shaft of the rotary table, that is, on the side that is caused to turn or the side that is caused to rotate (i.e., the output side).
However, if a clamping device is provided on the side that is caused to turn or the side that is caused to rotate (i.e., the output side), there are problems such as the construction of the output side becoming complex, and the output side becoming heavy.
In addition, consideration is required with regard to the construction of the clamping device. The shaft that is to be clamped is supported by a bearing or the like, and there is a possibility that misalignment of this shaft occurs. This misalignment can be, for example, axial displacements in which the axis of the shaft is displaced from the desired axis, or can be angular inclinations in which the axial orientation of the shaft is inclined from the desired axial orientation. In these cases, there is a discrepancy between the relative positions of the shaft and the clamping device. Such a discrepancy in the relative positions may also occur when there are misalignments due to displacement or inclination of the clamping device, even when there is no misalignment of the shaft. Consequently, there is a need for a clamping device that can properly clamp the shaft even in such a situation.